The 2002 Introduction of West Nile Virus Into Harris County, Texas, an Area Historically Endemic for St. Louis Encephalitis

Lillibridge, Kristy M.; Parsons, Ray E.; Randle, Yvonne; Rosa, A.P.A. Travassos da; Guzmán, Hilda; Siirin, Marina; Wuithiranyagool, Taweesak; Hailey, C.; Higgs, Stephen; Bala, Adil A.; Pascua, Rhia F.; Meyer, Tamra E.; Vanlandingham, Dana L.; Tesh, Robert B.

doi:10.4269/ajtmh.2004.70.676

Cited by 77 publications

(84 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In areas of Texas, 13.9% of the Cx. p. quinquefasciatus pools have tested positive for WNV, and minimum field infection rates of 3.3 per 1,000 have been recorded (29). There is now year-round WNV activity in Texas (30), a region with large bird populations and 86 species of mosquitoes (31,32).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Nonviremic transmission of West Nile virus

Higgs

Schneider

Vanlandingham

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

109

View full text Add to dashboard Cite

West Nile virus (WNV) is now the predominant circulating arthropod-borne virus in the United States with >15,000 human cases and >600 fatalities since 1999. Conventionally, mosquitoes become infected when feeding on viremic birds and subsequently transmit the virus to susceptible hosts. Here, we demonstrate nonviremic transmission of WNV between cofeeding mosquitoes. Donor, Culex pipiens quinquefasciatus mosquitoes infected with WNV were fed simultaneously with uninfected ''recipient'' mosquitoes on naïve mice. At all times, donor and recipient mosquitoes were housed in separate sealed containers, precluding the possibility of mixing. Recipients became infected in all five trials, with infection rates as high as 5.8% and no detectable viremia in the hosts. Remarkably, a 2.3% infection rate was observed when 87 uninfected mosquitoes fed adjacent to a single infected mosquito. This phenomenon could potentially enhance virus survival, transmission, and dispersion and obviate the requirement for viremia. All vertebrates, including immune and insusceptible animals, might therefore facilitate mosquito infection. Our findings question the status of dead-end hosts in the WNV transmission cycle and may partly explain the success with which WNV established and rapidly dispersed throughout North America.Culex ͉ mosquito vector

show abstract

Section: Resultsmentioning

confidence: 99%

“…25; www.cdc.gov͞ncidod͞dvbid͞westnile). Corvids represent only a small proportion of the total bird population present in most areas, but, for practical reasons, this bias toward the collection of moribund or dead corvids (29) and targeting of mosquito control efforts to areas where these birds are collected, has been widely implemented.…”

Section: Resultsmentioning

confidence: 99%

Nonviremic transmission of West Nile virus

Higgs

Schneider

Vanlandingham

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

109

View full text Add to dashboard Cite

show abstract

“…WNV caused an outbreak of encephalitis in New York in 1999 and SLEV was initially suspect to be the etiological agent (Briese et al 1999, Campbell et al 2002. Lillibridge et al (2004) reported that in Harris County, Texas, an endemic region for SLEV, WNV appeared and spread rapidly throughout the area. Surveillance data indicated that SLEV and WNV can coexist, despite their ecologic, antigenic and genetic similarities and both viruses will probably persist in Harris County.…”

Section: Discussionmentioning

confidence: 99%

Genetic characterization of St. Louis encephalitis virus isolated from human in São Paulo, Brazil

Santos

Sallum

Franco

et al. 2006

Mem. Inst. Oswaldo Cruz

View full text Add to dashboard Cite

(Calisher et al. 1989). The genome of flaviviruses contains a single-stranded positive sense RNA, about 10,800 nucleotides long that encodes 10 distinct proteins in a single reading frame (Chambers et al. 1990). SLEV is the etiologic agent of St. Louis encephalitis, a disease of epidemiological importance in North America. This virus was first isolated in the United States of America (US) in 1933, during an outbreak, which occurred in St. Louis and Kansas City, Mo. (Muckenfuss et al. 1934). In the US intermittent and unpredictable epidemics have been occurring during the last decades. The majority of SLEV infections is sub clinical or result in mild illness. The severity of infections is strongly dependent on the age of a patient, and the case fatality rate during epidemics ranges from 2% in young adults to more than 22% in the elders (Monath & Heinz 1996). In spite of being endemic in Central and South America, causing sporadic illness, occurrence of SLEV outbreaks is unknown (Spence 1980, Monath & Heinz 1996.The biological cycle of SLEV in nature involves primarily wild birds and several mosquito species; humans and other mammals are considered to be incidental hosts (Monath & Heinz 1996). In the US, Culicinae mosquitoes and birds, Passeriformes and Columbiformes, are involved in the dynamics of SLEV transmission. The transmission Financial support: Fapesp (no. 2004/07819-6) and CNPq (no. 305339/2003-6) cycle varies regionally, depending on the biology of mosquito species, virulence of SLEV strains and susceptibility to infection of vertebrate hosts (Monath & Tsai 1987, Day 2001, Reisen 2003. In Central and South America SLEV transmission cycle is not well defined, but it may include mosquito species of the genera Culex, Mansonia, Haemagogus, and Sabethes. A variety of bird taxa, including herons, egrets, and cormorant may be virus reservoirs (Spence 1980, Monath & Heinz 1996, Reisen 2003.The occurrence of SLEV in Brazil was recorded in 1953, by the finding of antibodies to this virus in residents of the Amazon Valley (Causey & Theiller 1958). A pool of mosquito Sabethes belisarioi, captured along the Belém-Brasília highway, was the source for the first isolation of a SLEV strain (Causey et al. 1964). Later in 1970 and 1978 two strains were recovered from human blood in Amazon region. In both cases the patients developed a febrile illness with jaundice, neither of them presenting neurological involvement (Pinheiro et al. 1981, Vasconcelos et al. 1998. SLEV was also found in the Southeast region of Brazil where it was isolated from wild birds, rodents, and sentinel mice during a surveillance program on arbovirus activity carried out in the state of São Paulo from 1967 to 1969 (Lopes et al. 1979).In the summer of 2004, after more than two decades of the last human Brazilian report, a clinical case of infection by SLEV was detected in the state of São Paulo. Epidemiologic data about the SLEV case was fully detailed by Rocco et al. (2005). Briefly, a patient, suffering from severe uncharacterized febrile illnes...

show abstract

“…pipiens complex, plays a role in WNV transmission analogous to the role of Cx. pipiens in the north 18,19,29,30 and Cx. pipiensquinquefasciatus hybrids in the middle latitudes of the United Figure 4.…”

Section: Discussionmentioning

confidence: 99%